Solid State Polymerization of Poly(Ethylene Furanoate) and Its Nanocomposites with SiO2and TiO2

Abstract

In the present study, poly(ethylene furanoate) (PEF) and its nanocomposites with SiO2and TiO2have been prepared and studied. Emphasis is given to study the effect of different nanoadditives, time, and temperature on solid state polymerization (SSP) of PEF. SSP is conducted at 180, 190, and 200 °C for 1, 2, 3.5, and 5 h under vacuum application. From intrinsic viscosity ([η]) measurements it is found that in all SSP samples the molecular weight increase is time and temperature dependent. The addition of nanofillers results in polymer production with slightly higher average molecular weight, especially at lower temperatures. A simple kinetic model is also developed and used to predict the time evolution of polymer's [η], as well as the carboxyl and hydroxyl content during the SSP. From the experimental measurements and the theoretical simulation it is proved that the presence of the nanoadditives results in higher transesterification kinetic rate constants. Moreover, compared to poly(ethylene terephthalate) (PET), the lower [η] of PEF, results in a much higher number of hydroxyl end groups and larger tranesterification and esterification reaction rates. Finally, the activation energy for the transesterification of PEF is found to be much higher compared to that of PET.image